>Hi Frank:
>
>Your SQL is erroneous, because ISNULL() only accepts 1 parameters and returns True/False, so in this case Thierry was right in using NVL(), but at the cost of always replacing the value (with the actual one or the new one, whatever)
>
>But if you are processing to much data and want the best performance, then Dragan's suggestion of building your UPDATE (with a series of IF..ENDIF for each field) is the best performing and does not add any noticeable cost of maintenance.


Used database is SQL Server so ISNULL() have the right syntax.
In TSQL ISNULL() function is equal to VFP NVL() function.